南京工程学院
自动化学院
本科毕业设计（论文）
题目： 数控螺纹车床控制系统硬件电路设计
专 业：
班 级：
学生姓名： 指导教师： 起迄日期：
设计地点： 工程实践中心
Graduation Design (Thesis)
Control System Hardware Circuit Design of Numerical
Control Thred Lathe
By CHEN Kai
Supervised by Associate Prof. HUA Maofa
School of Automation Nanjing Institute of Technology
June, 2008
南京工程学院自动化学院本科毕业设计（论文）
摘 要
本文详细地介绍了数控螺纹车床控制系统硬件电路的设计过程。该控制系统主要可分为六部分：CPU时钟及复位电路、存储器扩展电路、手动键盘和编辑键盘电路、I/O扩展电路、显示电路以及译码电路。控制系统选用MCS-51系列的8031作为主CPU；在存储器扩展电路设计中,选用27256芯片外扩了32K的程序存储器和 6264芯片外扩了8K的数据存储器，分别用于存放系统管理程序、数控加工程序以及运算数据；在手动键盘和编辑键盘设计中选用8155芯片的PA口和PC口作为行、列母线，扩展了矩阵式编辑键盘，用于程序和数据的输入或编辑，同时选用8031单片机的P1口扩展了手动键盘，用于系统启动、停止以及运动部件在X、Z轴方向的手动控制；在I/O口扩展电路设计中选用8255芯片扩展了输入输出口，用于接收和传送开关量及相关信息；在显示电路设计中，选用MCS-51系列的89C2051单片机作为从CPU，控制三排LED显示器，用于X轴、Z轴动态坐标以及相关数字的动态显示；此外选用74LS138译码器设计了相关芯片的片选信号译码电路。
综上所述，该设计电路简单、开发成本低、可靠性高，在此基础上，进一步完善硬件，并开发控制软件，对经济型数控螺纹车床，尤其是功能要求不高的经济型螺纹车床，具有一定的应用价值。
关键词：数控螺纹车床；控制系统；电路设计
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南京工程学院自动化学院本科毕业设计（论文）
ABSTRACT
This paper introduced the design process of the control system hardware circuit of numerical control thred lather in detail. The control system hardware circuit mainly includes six parts: CPU clock and reset circuit，memory expander, manual keyboard and editor keyboard circuit，I/O expander，display circuit as well as decoding circuit. The control system chose the 8031 singlechip of the MCS-51 series to be main CPU；In the design of memory expander, the chip of 27256 expanding program memory of 32K and the chip of 6264 expending the data-carrier storage of 8K outside, used for depositing the system administration procedure and CNC process program as well as operational datas respectively; The PA export and PC export of 8155 are used to expand the matrix editor keyboard circuit for inputting or editing the program and data, The P1 export of 8031 singlechip is used to expend the manual keyboard for starting and stopping system and moving the directional part in X or Z orientation; The chip of 8255 is chosen as I/O expander for receiving or transmitting information of on-off and related message. 892051 singlechip of the MCS-51series is chosen to control the three rows of LED monitor to display, used for showing the size of coordinates of X axis and Z axis and the related number of function word; In addition, the chip of 74LS164 is used to design decoding circuit for signal-election of related chips.
Total to say, the circuit is simple, the development cost is low, the reliability of system is high, in this foundation, further consummates the hardware, and develop the control software, then the design has the actual application value for economy numerical control thred lather, especially for those of which the demand of function isn’t high.
Key words： Numerical Control Thred Lathe; Control System; Circuit Design
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南京工程学院自动化学院本科毕业设计（论文）
目 录
第一章 绪论 .............................................................................................. 1
1.1 引言 .................................................................................................................. 1 1.2 选题背景与意义 .............................................................................................. 1 1.3 研究现状 .......................................................................................................... 2 1.4 本文的结构 ...................................................................................................... 3
第二章 数控螺纹车床控制系统硬件电路设计方案的拟定 .................. 4
2.1 控制对象及要求 .............................................................................................. 4 2.2 总体控制方案的拟定 ...................................................................................... 4 2.2.1 主CPU的选用 ....................................................................................... 4 2.2.2 外扩存储器的确定 ................................................................................. 5
2.2.3 显示电路的确定 ..................................................................................... 5 2.2.4 扩展键盘及I/O口电路的确定 ............................................................. 6
2.2.5 总体方案的结构框图 ............................................................................. 6
第三章 数控螺纹车床控制系统硬件电路设计 ...................................... 7
3.1 CPU时钟及复位电路设计 .............................................................................. 7 3.1.1 时钟电路设计 ......................................................................................... 7 3.1.2 复位电路设计 ......................................................................................... 7 3.2 存储器扩展电路设计 ...................................................................................... 8 3.2.1 程序存储器扩展电路设计 ..................................................................... 8 3.2.2 数据存储器扩展电路设计 ................................................................... 10 3.3 手动键盘和编辑键盘电路设计 .................................................................... 14 3.3.1 手动键盘电路设计 ............................................................................... 14 3.3.2 工作方式选择开关电路设计 ............................................................... 15 3.3.3 编辑键盘电路设计 ............................................................................... 16 3.4 I/O接口扩展电路设计 .................................................................................. 20 3.5 显示电路设计 ................................................................................................ 24 3.5.1 数字动态显示电路设计 ....................................................................... 24
3.5.2 功能显示电路设计 .............................................................................. 27 3.6 步进电机控制信号输出电路设计 ................................................................ 31 3.7 译码电路设计 ................................................................................................ 32 3.7.1 扩展芯片选择译码电路设计 ............................................................... 32
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